Simulated Seawater Flooding Reduces the Growth of Ten Vegetables

Abstract

Excessive salinity in soil and irrigation water in combination with waterlogging in coastal regions can significantly reduce the productivity of many agricultural crops. To evaluate the plant growth responses to simulated seawater (SSW) flooding, seedlings of 10 vegetables (broccoli, chinese cabbage, chinese greens, cucumber, eggplant, kale, radish, ‘Red Crunchy’ radish, spinach, and tomato) were flooded with SSW at electrical conductivity (EC) of 44.0 ± 1.3 dS·m−1 or tap water at EC of 0.8 ± 0.1 dS·m−1 for 24 hours and grown subsequently for 2 weeks in a greenhouse. Chinese greens and cucumber plants died shortly after flooding with SSW, whereas other vegetables exhibited various degrees of visible salt damage. Chinese cabbage suffered the strongest reduction, whereas spinach, tomato, and eggplant exhibited the least decrease in dry weight (DW) due to SSW flooding in comparison with their perspective control. Two weeks after flooding treatment with SSW, net photosynthetic rate of broccoli, kale, spinach, and tomato was reduced by 43% to 67%, transpiration rate by 35% to 66%, and stomatal conductance (gS) by 51% to 82%. In summary, spinach, eggplant, and tomato were the most tolerant, whereas chinese cabbage, chinese greens, and cucumber were the least tolerant to SSW flooding.